Skip to main content
VulnerabilityPublished Updated

CVE-2026-64286: Linux kernel · KVM: arm64: Clear __hyp_running_vcpu when flushing the pKVM hyp vCPU

Affects Linux kernelSource CVE Database V5

0

Not known to be exploited · CVSS 8.2 High · fixed in e8042f6e1d7befb2fb6b10a75918642bcd0acf9a : patch Linux kernel soon.

Data as of 26 Oct 2026, 13:47 UTC

CVSS 3.1 base score
8.2High
How severe the flaw is on the 0–10 CVSS scale.
EPSS
0.1% chance of exploitation in 30 days – higher than 7% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CISA SSVC
Exploitation
No evidence of active exploitation and no public proof of concept
Automatable
Attackers cannot reliably automate steps 1–4 of the kill chain
Technical impact
Total control over the software or total information disclosure

CISA SSVC assessment, 2026-10-16.

Patch
Available – fixed in e8042f6e1d7befb2fb6b10a75918642bcd0acf9a, dfaef40d8a1533940fc1af788d70fce07362b4ce, d4f4d61715d1061ba83b88196a3605662be30750 +2
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H

Exploitation evidence

  1. Disclosed: evidence found.

    CVE published 25 Jul 2026

  2. Detectable: no evidence on record.

    No public nuclei template indexed

  3. Weaponised: no evidence on record.

    No public exploit code indexed in Metasploit or Exploit-DB

  4. Exploited in the wild: no evidence on record.

    Not in CISA KEV and no source reports exploitation

  5. Observed by OffSeq Mirage: no evidence on record.

    No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

ProductAffectedFixed in
LinuxLinuxAffected
  • ≥ be66e67f175096f283c9d5614c4991fc9e7ed975, < e8042f6e1d7befb2fb6b10a75918642bcd0acf9a
Fixed in
  • e8042f6e1d7befb2fb6b10a75918642bcd0acf9a
LinuxLinuxAffected
  • ≥ be66e67f175096f283c9d5614c4991fc9e7ed975, < dfaef40d8a1533940fc1af788d70fce07362b4ce
Fixed in
  • dfaef40d8a1533940fc1af788d70fce07362b4ce
LinuxLinuxAffected
  • ≥ be66e67f175096f283c9d5614c4991fc9e7ed975, < d4f4d61715d1061ba83b88196a3605662be30750
Fixed in
  • d4f4d61715d1061ba83b88196a3605662be30750
LinuxLinuxAffected
  • ≥ be66e67f175096f283c9d5614c4991fc9e7ed975, < 477145860dba4c30f0b4e36f02f4c5291c1c888b
Fixed in
  • 477145860dba4c30f0b4e36f02f4c5291c1c888b
LinuxLinuxAffected
  • ≥ be66e67f175096f283c9d5614c4991fc9e7ed975, < 6bea2f8becdb20d34378493c3b77a9b9cf8c6cfa
Fixed in
  • 6bea2f8becdb20d34378493c3b77a9b9cf8c6cfa
LinuxLinuxAffected
  • =6.2
Fixed in–

Description

In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: Clear __hyp_running_vcpu when flushing the pKVM hyp vCPU flush_hyp_vcpu() copies the host vCPU context into the hyp's private vCPU on every run. ctxt_to_vcpu() expects a guest context to have a NULL __hyp_running_vcpu, which is only ever set on the host context, so that it resolves the vCPU via container_of(). While this is generally the case, flush_hyp_vcpu() copies the context verbatim and does not enforce this, so a value provided by the host is dereferenced at EL2 (host -> EL2). Fix by clearing __hyp_running_vcpu after the copy.

References

Community reviews

Loading reviews…